JEE Exam  >  JEE Questions  >  How many natural numbers are their from 1 to ... Start Learning for Free
How many natural numbers are their from 1 to 1000 which have none of their digits repeated.
Correct answer is '738'. Can you explain this answer?
Most Upvoted Answer
How many natural numbers are their from 1 to 1000 which have none of t...
Solution:

To find the number of natural numbers from 1 to 1000 which have none of their digits repeated, we can follow the below steps:

Step 1: Count the numbers with a single digit
- There are 9 such numbers (1, 2, 3, 4, 5, 6, 7, 8, 9)

Step 2: Count the numbers with two digits
- The first digit can be any of the 9 digits (excluding 0)
- The second digit can be any of the 9 remaining digits (excluding the first digit)
- So, there are 9 x 9 = 81 such numbers

Step 3: Count the numbers with three digits
- The first digit can be any of the 9 digits (excluding 0)
- The second digit can be any of the 9 remaining digits (excluding the first digit)
- The third digit can be any of the 8 remaining digits (excluding the first two digits)
- So, there are 9 x 9 x 8 = 648 such numbers

Step 4: Add up the numbers from all the steps
- Total number of natural numbers from 1 to 1000 which have none of their digits repeated = 9 + 81 + 648 = 738

Therefore, the correct answer is '738'.
Free Test
Community Answer
How many natural numbers are their from 1 to 1000 which have none of t...
Explore Courses for JEE exam
How many natural numbers are their from 1 to 1000 which have none of their digits repeated.Correct answer is '738'. Can you explain this answer?
Question Description
How many natural numbers are their from 1 to 1000 which have none of their digits repeated.Correct answer is '738'. Can you explain this answer? for JEE 2025 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about How many natural numbers are their from 1 to 1000 which have none of their digits repeated.Correct answer is '738'. Can you explain this answer? covers all topics & solutions for JEE 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for How many natural numbers are their from 1 to 1000 which have none of their digits repeated.Correct answer is '738'. Can you explain this answer?.
Solutions for How many natural numbers are their from 1 to 1000 which have none of their digits repeated.Correct answer is '738'. Can you explain this answer? in English & in Hindi are available as part of our courses for JEE. Download more important topics, notes, lectures and mock test series for JEE Exam by signing up for free.
Here you can find the meaning of How many natural numbers are their from 1 to 1000 which have none of their digits repeated.Correct answer is '738'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of How many natural numbers are their from 1 to 1000 which have none of their digits repeated.Correct answer is '738'. Can you explain this answer?, a detailed solution for How many natural numbers are their from 1 to 1000 which have none of their digits repeated.Correct answer is '738'. Can you explain this answer? has been provided alongside types of How many natural numbers are their from 1 to 1000 which have none of their digits repeated.Correct answer is '738'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice How many natural numbers are their from 1 to 1000 which have none of their digits repeated.Correct answer is '738'. Can you explain this answer? tests, examples and also practice JEE tests.
Explore Courses for JEE exam

Top Courses for JEE

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev